Traditional Eyewear and Hinges
Eyewear is both functional and fashionable. Some frame designs are considered classic and timeless, such as wayfarers, the cat eye design, aviators, and the like. Eyewear designers are continuously pushing fashion boundaries to keep up with and to satisfy the public's constantly changing tastes. Whether used for prescription or for common sun filtering lenses, eyewear is traditionally made through subtractive manufacturing of left and right temple bars, hinges, and the lens frame. The cost of materials lost to the manufacturing process and bulk production is often passed on to the consumer.
Eyeglasses were initially designed to be held to the face or balanced on the nose. The addition of temple bars created a need for hinges to absorb mechanical forces like twisting, bending, and stretching that act on the frame. The traditional hinge has the inherent drawbacks of breakage at the lens frame, temple bar, or at the middle of the hinge where the screw is. Any part that is lost or broken must be replaced or the eyewear must be discarded.
Hinges connect temple bars to the lens frame on a pair of eye glasses and swivels the temple bars from the open to the closed position. Common eyewear hinges include the barrel hinge, interlocking hinges, spring hinges or breakaway hinges. FIG. 1 depicts a traditional barrel hinge 10 with two hinge parts 11a, 11b, one having an even number of evenly spaced knuckles 11a and the other having an odd number of evenly spaced knuckles 11b. Each hinge part 11a, 11b is perpendicularly affixed to the outer corners of the lens frame 12 and to a corresponding temple bar 13. One hinge part 11b is mounted to the temple bar 13 with screws 14 and a brace 15. The other hinge part 11a is mounted into the lens frame 12 with screws 14 and a brace 15. The knuckles of each part 11a, 11b are interleaved and form a hollow cylinder that is threaded and can accept a screw 14. All hinge 10 parts are manufactured separately and assembled for use.
3D Modeling & Printing for Additive Manufacturing
The continued refining of 3D Printing has opened a world of possibilities for additive manufacturing. With digital models, 3D Printing can make cost effective three-dimensional solid objects of virtually any shape. This method of manufacturing is additive, where successive layers of a material are laid down in different shapes according to digital instructions.
3D Printing is also considered distinct from traditional machining techniques, which mostly rely on the removal of material by methods such as cutting or drilling, the subtractive processes. With additive manufacturing, objects can be used anywhere throughout the product life cycle, from pre-production (i.e. rapid prototyping) to full-scale production (i.e. rapid manufacturing), in addition to tooling applications and post-production customization. 3D printing technology is used with applications in architecture, industrial design, automotive, aerospace, military, civil engineering, medical industries, biotech, fashion, footwear, jewelry, eyewear, education, geographic information systems, and many other fields.
The present invention takes advantage of 3D printers to construct a one piece eyewear having hinges defined by parametric contours that mimic the rotational motion and force absorption properties of traditional mechanical hinges. The entire eyeglass frame is a continuous construct. The temple bars open and close at a designated point of weakness placed in the inside corner of the frame, being the flexible hinge of the present invention.
U.S. Pat. No. 3,526,449 to Bolle et al. discloses sunglasses being a one piece eyewear molded to have optically curved lenses.
U.S. Pat. No. 5,059,017 to Bennato et al. discloses a bellow like hinge having lugs that connect the lens frame to temple rods.
US Patent Application No. 2015/0039133 filed by Kanada discloses the basic concepts of 3D printing including the use of computer instructions and materials that can be used for printing constructs.
US Patent Application No. 2014/0185002 filed by McNeal discloses eyewear frames having contoured temples.
U.S. Pat. No. 5,518,680 to Cima, L. et al. discloses various 3D printing techniques, which is incorporated herein by reference.
US Patent Application No. 2015/0097315 filed by DeSimone, J. M. et al. discloses a 3D printing technique called Continuous Liquid Interface Production (CLIP), which is incorporated herein by reference.
None of the cited art discloses the advantages of making concealed hinges that are flexible parametric curves for eyewear by additive manufacturing. Therefore, there is a need for a one piece eyewear layered through 3D printing having a concealed hinge that mimics the rotational motion and stress bearing properties of traditional hinges.